Various weight measuring devices for measuring the weight of the living body have been conventionally proposed. The proposed device for measuring the weight includes a device in which the function of the weight scale is provided to the body composition meter, where a device for measuring the weight of a pet is proposed as a device defining a reference value through calibration beforehand (see patent document 1). Such pet automatic weight measurement system is described to use the reference value obtained through calibration using a spindle of a predetermined weight in advance.
The 0 kg state that becomes the reference value changes by the installed location, the tilt, and the like of the weight measuring device. The pet automatic weight measurement system described above obtains the reference value through calibration in advance, and thus has error caused by the installing environment after factory shipment.
Measurement of 0 kg is generally carried out before starting the weight measurement to ensure the precision for the weight measuring device. In this case, however, the measurement takes time and the measurement cannot be started right away. Thus, the problem in that each measurement takes time arises.
Patent Document 1: Japanese Unexamined Patent Publication No. 2007-330200